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Showing posts from October, 2016

eBEEF Monday: Economically Relevant Traits

Economically relevant traits (ERTs) are those that are directly associated with either a cost or a source of revenue.  Not all Expected Progeny Differences (EPDs) represent traits that are ERTs, and instead represent indicator traits. It is important for producers to know the difference between ERTs and indicator traits when making selection decisions.

For more information, see the eBEEF.org factsheet "Economically Relevant Traits."

Beefmaster Breeders United Convention: EPDs and Selection Indexes

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Matt Spangler
University of Nebraska-Lincoln

In the past, the only way we made improvement was through visual appraisal.

As the picture above shows, we can make a change, but how many of us want to wait 100 years?

Improvement can be accomplished through management and genetics.

In the past we (animal breeding scientist) have probably done a disservice to the industry by producing lots of EPDs, then dumping those in beef producers lap and then expect you all to make meaningful decisions with them. In some situations, this may be as valuable as a free cat.

There are many factors that can influence an animals record, for example a weaning weight. Weaning weight may be affected by age of the calf, age of the dam, how much it was feed, and other environmental factors.

So, we need to compare animals to their contemporaries, Contemporaries are animals of the same sex, raised at the same ranch with the same management. We can calculate a ratio of how different from the contemporary group each …

NBCEC Brown Bagger: Implementation of single step methodologies at Angus Genetics, Inc.

Steve Miller
AGI

Angus Genetic Services provides evaluations for AAA, CAA, and Charolais breed associations.

"The ship has sailed on using genomics. Breeders are using it now, and seeing the benefits of it," said Miller.

Previously at AGI, they have been using a two-step approach. In this method, a genomic prediction is created and then is used as an indicator trait for EPD estimation. The calibration data set size has increased dramatically as Angus breeders have used genomic-enhanced EPDs.

The orgininal method of incorporting genomic predictions as correlated trait.

In the future, we will stop referring to genomic-enhanced EPDs. We don't refer to EPDs as pedigree-enhanced or performance-enhanced, we simply refer to them as EPDs. In the future use of genomic data in genetic prediction will become so routine that we will simply call them EPDs.

Is the Animal Model Obsolute?


In single-step genomic prediction, we combine the measures of relatedness from pedigree data with t…

NBCEC Brown Bagger: Implementation of single step methodologies at International Genetic Solutions

Dr. Mahdi Saatchi
International Genetic Solutions

IGS performs genetic evaluations for 12 breed associations from North America.
IGS has over 16 million animals in their database and is adding over 400,000 animals per yer.
IGS has 84,197 animals with genotypes. Simmental makes up about 40,000 of these genotypes.

Currently at IGS they blend the molecular breeding value (MBV, the genomic prediction) with the multi-breed international cattle evaluation. This is more like the blending that occurs with selection indexes.

Single-step genomic prediction allows information from genotyped animals to be spread to related animals in the data set.
Also, multiple-step genomic predictions were often trained on breeding values, and any errors in the estimation of the breeding values influenced the genomic prediction.

There are two approaches to single-step genetic evaluation. Single-step BLUP uses a breeding value model. Single-step Bayesian Regression uses a marker effects model.

In Single-step Bay…

eBEEF Monday: How to Get Started with DNA Testing

This fact sheet goes through the fundamentals of how and when producers might use DNA testing in beef cattle production.  It covers the different types of tests that are available, how to submit samples and to whom, and what to do with the results.

For more information, see the eBEEF.org factsheet "How to Get Started with DNA Testing".

eBEEF Monday: Recent Developments in Genetic Evaluations and Genomic Testing

The application of genomics to improve the accuracy of EPDs is a rapidly developing field. There are ongoing improvements in genotyping and sequencing technologies, statistical methods to increase the correlation between genomic predictions and true genetic merit, and the computing systems to handle the large datasets associated with animal breeding. One thing still remains true in the genomic age and that is the need to collect accurate phenotypic records. It is essential to ensure performance data, pedigree, and DNA information are recorded and reported accurately. Genomic predictions will only be as reliable as the data upon which they are based.  Although it might seem like the genomics era could signal the end of performance recording, the opposite is true. Now more than ever, it is important that producers accurately report data, and ensure that animals which are genotyped are correctly identified so that their information can contribute towards improving the accuracy of the gen…

eBEEF Monday: Recent Developments in Genetic Evaluations and Genomic Testing

The application of genomics to improve the accuracy of EPDs is a rapidly developing field. There are ongoing improvements in genotyping and sequencing technologies, statistical methods to increase the correlation between genomic predictions and true genetic merit, and the computing systems to handle the large datasets associated with animal breeding. One thing still remains true in the genomic age and that is the need to collect accurate phenotypic records. It is essential to ensure performance data, pedigree, and DNA information are recorded and reported accurately. Genomic predictions will only be as reliable as the data upon which they are based.  Although it might seem like the genomics era could signal the end of performance recording, the opposite is true. Now more than ever, it is important that producers accurately report data, and ensure that animals which are genotyped are correctly identified so that their information can contribute towards improving the accuracy of the gen…

eBEEF Monday: Recent Developments in Genetic Evaluations and Genomic Testing

The application of genomics to improve the accuracy of EPDs is a rapidly developing field. There are ongoing improvements in genotyping and sequencing technologies, statistical methods to increase the correlation between genomic predictions and true genetic merit, and the computing systems to handle the large datasets associated with animal breeding. One thing still remains true in the genomic age and that is the need to collect accurate phenotypic records. It is essential to ensure performance data, pedigree, and DNA information are recorded and reported accurately. Genomic predictions will only be as reliable as the data upon which they are based.  Although it might seem like the genomics era could signal the end of performance recording, the opposite is true. Now more than ever, it is important that producers accurately report data, and ensure that animals which are genotyped are correctly identified so that their information can contribute towards improving the accuracy of the gen…

eBEEF Monday: Commercial Replacement Heifer Selection

Heifer selection is an important aspect of commercial beef operations, but unlike bull selection must be done without the aid of Expected Progeny Differences. This factsheet discusses considerations when making heifer selections, including available genomics tools and the importance of sire selection when replacement heifers are to be retained.

For more information, see the eBEEF.org factsheet.

NCBEC Brown Bagger: Potential impacts of functional variants on national cattle evaluation

Larry Kuehn
USDA-MARC

When we go from less than a thousand animals to several thousands of animals, genomic predictions can explain about 50% of the genetic variance for important traits. Genomic prediction is working and providing tremendous benefits to seedstock and commercial producers.

But, we still struggle with genomic predictions with very little data recording and genomic predictions that work well across breeds.

Two methods are used to use genomics in national cattle evaluation. With the genomic pedigree method you track genetic effects more accurately than with pedigree data. With the second method you are relying on linkage on chromosomes between the DNA markers and the variants responsible for the differences (causal mutations).

The linkage signal between DNA markers and causal variants breaks down over generations due to recombination (switching) between paternal and maternal chromosomes. Because this linkage breaks down over time is part of the reason genomic prediciton…

eBEEF.org Monday: The Genetics of Horned, Polled and Scurred Cattle

The condition of horned, polled or scurred in cattle has important economic and welfare considerations, but is poorly understood. This factsheet explores the genetic aspects of these conditions, their relationships with each other and how to manage them in your breeding program.
For more information see the factsheet "The Genetics of Horned, Polled and Scurred Cattle" on eBEEF.org.